Born at Belper, Derbys, the sister of Sir John Bamford-Slack. In 1895 she became secretary of the British Women's Temperance Union and the World Women's Christian Temperance Union founded by her close friend Frances Willard. She travelled throughout the British Isles and the world, speaking and preaching in churches of many denominations, but especially WM, and was the first woman allowed to preach in Wesley's Chapel, London. During the Grindelwald conference of 1895 she was the principal speaker in a lively debate on the changing role of women in society ('the Revolt of the Daughters'). She wrote My Travels in India (1918) and People I Have Met and Places I have Been (1941) and died at Sheffield in 1940.